Here is a site dedicated to your question.
Keep in mind there is still a lot of unknowns about E85 gas. A lot of people have claimed to have had severe corrosion due to the way E85 effects fuel systems. Other people have claimed worse performance and MPG in fuel flex vehicles compared to regular gas. I personally cannot say as I've never used it, however those are comments I've heard first hand from people that have used it and had problems with it.